BUG: Multi-column explode does not raise ValueError for length-1 and empty list #53512
Description
Pandas version checks
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I have checked that this issue has not already been reported.
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I have confirmed this bug exists on the latest version of pandas.
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I have confirmed this bug exists on the main branch of pandas.
Reproducible Example
import pandas as pd
df = pd.DataFrame([[[1], []]], columns=["A", "B"])
df.explode(column=["A", "B"]) # Does not raise ValueError: columns must have matching element countsIssue Description
- The lists
[1]and[]are of unequal length, thus I expect asValueErroras is the case for length-2 vs length-0 lists ([0, 1]vs[]). - I checked pandas version '1.5.2' where the ValueError is raised as expected.
- I think this is related to BUG: df.explode mulitcol with Nan+emptylist #49680, where
mylenis assigned 1 for both the empty and the length-1 list:Line 9284 in 37783d4
Expected Behavior
import pandas as pd
df = pd.DataFrame([[[1], []]], columns=["A", "B"])
df.explode(column=["A", "B"]) # Raises ValueError: columns must have matching element countsInstalled Versions
Details
INSTALLED VERSIONS
commit : 37783d4
python : 3.10.8.final.0
python-bits : 64
OS : Linux
OS-release : 5.15.49-linuxkit
Version : #1 SMP Tue Sep 13 07:51:46 UTC 2022
machine : x86_64
processor :
byteorder : little
LC_ALL : None
LANG : C.UTF-8
LOCALE : en_US.UTF-8
pandas : 2.1.0.dev0+900.g37783d4bcb
numpy : 1.24.3
pytz : 2023.3
dateutil : 2.8.2
setuptools : 63.2.0
pip : 23.1.2
Cython : 0.29.33
pytest : 7.3.1
hypothesis : 6.75.9
sphinx : 6.2.1
blosc : 1.11.1
feather : None
xlsxwriter : 3.1.2
lxml.etree : 4.9.2
html5lib : 1.1
pymysql : 1.0.3
psycopg2 : 2.9.6
jinja2 : 3.1.2
IPython : 8.13.2
pandas_datareader: None
bs4 : 4.12.2
bottleneck : 1.3.7
brotli :
fastparquet : 2023.4.0
fsspec : 2023.5.0
gcsfs : 2023.5.0
matplotlib : 3.7.1
numba : 0.57.0
numexpr : 2.8.4
odfpy : None
openpyxl : 3.1.2
pandas_gbq : None
pyarrow : 12.0.0
pyreadstat : 1.2.1
pyxlsb : 1.0.10
s3fs : 2023.5.0
scipy : 1.10.1
snappy :
sqlalchemy : 2.0.15
tables : 3.8.0
tabulate : 0.9.0
xarray : 2023.5.0
xlrd : 2.0.1
zstandard : 0.21.0
tzdata : 2023.3
qtpy : None
pyqt5 : None